class BT {
 def h(x : Int) : Int = 
   /*precondition x == 3 
     postcondition res == 3
    */
   x

 def isGood(): Boolean = (this : BT) match {
   case _ if (this.h(this.h(3)) > 0) => true
  }
}

object Simple {

  def main(args: Array[String]): Unit =
    true
}